Implement --purge_user_libs konanc and cinterop flag

backend.native/cli.bc/src/org/jetbrains/kotlin/cli/bc/K2Native.kt

@@ -120,6 +120,8 @@ class K2Native : CLICompiler<K2NativeCompilerArguments>() {
                 put(PRINT_LOCATIONS, arguments.printLocations)
                 put(PRINT_BITCODE, arguments.printBitCode)
 
+                put(PURGE_USER_LIBS, arguments.purgeUserLibs)
+
                 put(VERIFY_IR, arguments.verifyIr)
                 put(VERIFY_DESCRIPTORS, arguments.verifyDescriptors)
                 put(VERIFY_BITCODE, arguments.verifyBitCode)

backend.native/cli.bc/src/org/jetbrains/kotlin/cli/bc/K2NativeCompilerArguments.kt

@@ -121,6 +121,9 @@ class K2NativeCompilerArguments : CommonCompilerArguments() {
     @Argument(value = "--print_locations", description = "Print locations")
     var printLocations: Boolean = false
 
+    @Argument(value = "--purge_user_libs", description = "Don't link unused libraries even explicitly specified")
+    var purgeUserLibs: Boolean = false
+
     @Argument(value = "--time", description = "Report execution time for compiler phases")
     var timePhases: Boolean = false
 

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanConfig.kt

@@ -73,6 +73,9 @@ class KonanConfig(val project: Project, val configuration: CompilerConfiguration
     val moduleId: String
         get() = configuration.get(KonanConfigKeys.MODULE_NAME) ?: File(outputName).name
 
+    internal val purgeUserLibs: Boolean
+        get() = configuration.getBoolean(KonanConfigKeys.PURGE_USER_LIBS)
+
     private val libraryNames: List<String>
         get() = configuration.getList(KonanConfigKeys.LIBRARY_FILES)
 
@@ -95,7 +98,7 @@ class KonanConfig(val project: Project, val configuration: CompilerConfiguration
     fun librariesWithDependencies(moduleDescriptor: ModuleDescriptor?): List<KonanLibraryReader> {
         if (moduleDescriptor == null) error("purgeUnneeded() only works correctly after resolve is over, and we have successfully marked package files as needed or not needed.")
 
-        return immediateLibraries.purgeUnneeded().withResolvedDependencies()
+        return immediateLibraries.purgeUnneeded(this).withResolvedDependencies()
     }
 
     private val loadedDescriptors = loadLibMetadata()

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/KonanConfigurationKeys.kt

@@ -85,6 +85,8 @@ class KonanConfigKeys {
                 = CompilerConfigurationKey.create("compiler output kind")
         val PROPERTY_FILE: CompilerConfigurationKey<String?> 
                 = CompilerConfigurationKey.create("override default property file path")
+        val PURGE_USER_LIBS: CompilerConfigurationKey<Boolean>
+                = CompilerConfigurationKey.create("purge user-specified libs too")
         val REPOSITORIES: CompilerConfigurationKey<List<String>>
                 = CompilerConfigurationKey.create("library search path repositories")
         val RUNTIME_FILE: CompilerConfigurationKey<String?> 

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/library/impl/KonanLibraryReaderImpl.kt

@@ -16,6 +16,7 @@
 
 package org.jetbrains.kotlin.backend.konan.library.impl
 
+import org.jetbrains.kotlin.backend.konan.KonanConfig
 import org.jetbrains.kotlin.backend.konan.library.KonanLibraryReader
 import org.jetbrains.kotlin.backend.konan.createInteropLibrary
 import org.jetbrains.kotlin.backend.konan.serialization.emptyPackages
@@ -98,5 +99,6 @@ class LibraryReaderImpl(var libraryFile: File, val currentAbiVersion: Int,
 
 }
 
-internal fun <T: KonanLibraryReader> List<T>.purgeUnneeded(): List<T> = this.filter{ !it.isDefaultLibrary || it.isNeededForLink }
+internal fun <T: KonanLibraryReader> List<T>.purgeUnneeded(config: KonanConfig): List<T> =
+        this.filter{ (!it.isDefaultLibrary && !config.purgeUserLibs) || it.isNeededForLink }
 

backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/ContextUtils.kt

@@ -328,7 +328,7 @@ internal class Llvm(val context: Context, val llvmModule: LLVMModuleRef) {
     }
 
     val librariesToLink: List<KonanLibraryReader> get() = context.config.immediateLibraries
-            .filter { !it.isDefaultLibrary || it in usedLibraries }
+            .filter { (!it.isDefaultLibrary && !context.config.purgeUserLibs) || it in usedLibraries }
             .withResolvedDependencies()
 
     val librariesForLibraryManifest: List<KonanLibraryReader> get() {